A systematic review of the patient burden of Crohn's disease-related rectovaginal and anovaginal fistulas

Background: Crohn's disease (CD)-related rectovaginal fistulas (RVFs) and anovaginal fistulas (AVFs) are rare, debilitating conditions that present a substantial disease and treatment burden for women. This systematic literature review (SLR) assessed the burden of Crohn's-related RVF and AVF, summarizing evidence from observational studies and highlighting knowledge gaps.

Methods: This SLR identified articles in PubMed and Embase that provide data and insight into the patient experience and disease burden of Crohn's-related RVF and AVF. Two trained reviewers used pre-specified eligibility criteria to identify studies for inclusion and evaluate risk of bias using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for observational studies.

Results: Of the 582 records identified, 316 full-text articles were assessed, and 16 studies met a priori eligibility criteria and were included. Few epidemiology studies were identified, with one study estimating the prevalence of RVF to be 2.3% in females with Crohn's disease. Seven of 12 treatment pattern studies reported that patients had or required additional procedures before and/or after the intervention of interest, demonstrating a substantial treatment burden. Seven of 11 studies assessing clinical outcomes reported fistula healing rates between 50 and 75%, with varying estimates based on population and intervention.

Conclusions: This SLR reports the high disease and treatment burden of Crohn's-related RVF and AVF and identifies multiple evidence gaps in this field. The literature lacks robust, generalizable data, and demonstrates a compelling need for substantial, novel research into these rare and debilitating sequelae of CD. Registration The PROSPERO registration number for the protocol for this systematic literature review is CRD42020177732.